Ultrasound imaging is becoming increasingly popular as a replacement for X-ray imaging techniques due to the health hazards associated with x-ray radiation. In ultrasound imaging, one or more emitting piezoelectric transducers are placed into contact with the patient's skin and energized to generate one or more ultrasound signals. The ultrasound signals are reflected by changes in tissue density, such as by the organ of interest, and the reflected signals received by one or more receiving piezoelectric transducers. The collected data, namely the time (measured from the time of signal emission) required by the signal to be received by the receiving piezoelectric transducer(s) and the intensity of the received signal, can be combined with the position (x,y,z) and orientation (alpha, beta, gamma) of the probe to generate a plurality of two-dimensional scanning or imaging planes. To form a three-dimensional image of the organ, an output volume containing a number of elements is generated. A gray-scale value is assigned to each element by sequentially and independently processing each of the scanning planes.
In designing an efficient three-dimensional ultrasound imaging system, there are a number of considerations. First, image data should not be ignored during generation of the output volume. The quality of the image can be negatively impacted by the failure to consider image data in the scanning planes. Second, the processing of the image data in all of the scanning planes should be performed quickly and with the least amount of memory space. Third, the user should have the option of utilizing a number of different algorithms to process the image data in the scanning planes. This flexibility permits the user to select the algorithm producing the highest quality image.